<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="{{ url_for('static', filename='js/jquery-3.3.1/jquery-3.3.1.js') }}">
    </script>
    <script>
        if(jQuery) {
            alert('jquery 已加载');
        }
        else {
            alert('jquery is wrong');
        }
    </script>
</head>
    <!--
    <script type="text/javascript" src="static/js/jquery-3.3.1/jquery-3.3.1.js">
    </script>
    -->
    <img src="{{ url_for('static', filename='./car.jpg')}}">
    <link rel="stylesheet" href="{{ url_for('static',filename='./car.css')}}">

<body>

</body>
</html>